Power
Motive
The motive, power, is only available in The Sims 2: Open for Business Expansion Pack. Only a Servo will have it.
The Power motive is like the Energy motive for a Sim. Servos can fill this need the same as a Sim can, or while it is daylight they can step outside and use the "Recharge" command.
If this need get too low Servo will go berserk and will require repairs by a Sim with a high Mechanical Skill.
Aspiration
The Aspiration called Power is unused but can be accessed by the Sim Modder with boolprop testingcheatsenabled. An image doesn't exist for it.